1. Field of the Invention
The present invention relates to image output, and particularly to an adjustment of a binocular parallax for each stereoscopic image frame of a stereoscopic video.
2. Description of the Related Art
A stereoscopic image processing device in Japanese Patent Application Laid-Open No. 2004-221699 (hereinafter referred to as PTL 1), when a displayed subject reaches a limit parallax, generates parallax images in accordance with acquired adequate parallax information, such that the adequate parallax is implemented in subsequent stereoscopic display. The control of the parallax is implemented by going back to three-dimensional data and optimally setting a camera parameter. Here, a two-dimensional image generation unit of the stereoscopic image processing device calculates a depth Fxy that meets the adequate parallax. When the range of the depth is K1 to K2 and the depth value of each pixel is Gxy, Fxy=J1+(Gxy−K1)×(J2−J1)/(K2−K1) holds. In the case where Fxy is not an integer, a rounding or a process for decreasing an approximation parallax is performed.
A three-dimensional image processing device in Japanese Patent Application Laid-Open No. 6-028452 (hereinafter referred to as PTL 2) provides an observation viewpoint sensor to detect an observation viewpoint of a facing observer, on a display device to display a three-dimensional image shown in perspective by a viewpoint coordinate system, and a computer moves the viewpoint coordinate system of the display image, in tune with the observation viewpoint detected by the observation viewpoint sensor. Thereby, the perspective viewpoint of the three-dimensional image to be displayed on the display device is moved so as to follow the observation viewpoint of the observer, and the image display is performed such that the perspective viewpoint always accords with the observation viewpoint.
A three-dimensional image display device in Japanese Patent Application Laid-Open No. 9-238369 (hereinafter referred to as PTL 3) includes a viewpoint detection device to detect a viewpoint position of an observer, a picture generation device to generate two pictures having a parallax for the left and right eyes, a picture display device to display the two pictures for individually projecting them, and a picture projection device to individually project the two displayed pictures to the left and right eyes of the observer. The picture generation device generates pictures that reflect the change in an observation direction for an observation object corresponding to the movement of the viewpoint of the observer, based on output signals of the viewpoint detection device. Furthermore, the picture generation device generates pictures of an imaginary body that reflect the change in the observation direction for the observation object corresponding to the movement of the viewpoint of the observer, and that have a parallax for the left and right eyes of the observer, based on output signals of the viewpoint detection device.
A stereoscopic image display method in Japanese Patent Application Laid-Open No. 8-327948 (hereinafter referred to as PTL 4), by a configuration that includes a display unit to provide a liquid crystal shutter in front of a display device and dispose a lenticular lens in front of the liquid crystal shutter, and a control unit to which a viewpoint position of an observer is input, displays a parallax image corresponding to the right eye and left eye on the display device by time division, and synchronously with the parallax image, changes the width and position of a light-transmitting part of the liquid crystal shutter in response to the viewpoint position of the observer, allowing the parallax image to be observed by a corresponding eye through the lenticular lens.